Torque converter



Nov. 4, 1952 E. J. THURBER ToaQuE CONVERTER 3 Sheets-Sneet 1 Filed Oct. 6. 1948 N NaN Wsw 5 Y E N R O T T A Nov. 4, 1952 E. .1.l THURBER -2,616,303

ToRQuE CONVERTER Filed Oct. 6, 1948 3 SheetS-Sneet 2 E dwar' d T. ThLrl-"h er@ 4 ATTORNEYS Nov. 4, 1952 E. J. THuRBl-:R

TORQUE CONVERTER 3 Sheets-Sheet 3 Filed 061'.. 6. 1948 Patented Nov. 4, 1952 TRQUE CONVERTER Edward J. Thurber, New Orleans, La., assignor to The Thurber Corporation, New Orleans, La., a

corporation of Louisiana Application October 6, 1948, Serial No. 53,026

(Cl. 'i4-472) 37 Claims. l

rThis invention relates to torque converters and more particularly to hydraulic variable speed transmissions of the type wherein the torque is multiplied and the power is transmitted through the cooperative effect of impeller drive members, turbine driven members and the circulation oi a working fluid in a closed path through these members.

In conventional torque converters a stationary reactionary member is employed between the turbine and impeller elements. The reason for utilizing such a member is that when the iiuid exhausts from the turbine, it is moving in a direction opposite to the direction of rotation of the impeller, and the iluid must be turned in the direction of the impeller before it reaches the latter. Such stationary reactionary members employ stationary varies having a fixed profile. Such an arrangement would be satisfactory if the exhaust from the' turbine held a constant pattern. In operation however, the fluid exhaust pattern is not constant but varies with the speed of the turbine. As a result, a xed vane prole in a stationary reactionary member cannot accommodate or adjust itself in order to meet the varying uid exhaust pattern. The result is, that the stationary reactionary member blocks the free flow of fluid, causing the generation of heat, a decrease of the uid velocity and a lowering of the einciency of the converter.

In the present invention, power is transmitted from the driving members to the driven members through a system of primary and secondary impeller and turbine elements, the arrangement being such that the primary impeller and turbine elements rotate in one direction, the secondary impeller and turbine elements rotate in the opposite direction, and both sets of impellers and turbines are combined into a common drive. Due to the circulation of a working fluid through these parts in a closed path, the transmission of power is readily effected. More particularly, the invention insures an arrangement of the driving members or impellers and the driven members or turbines so that the working fluid leaves one of the members and passes directly to the next member. When the fluid reaches the secondary impeller, the latter is rotating in the same direction as the fluid exhaust from the primary turbine. In the secondary impeller, due to the higher peripheral speed, the velocity of the fluid will be increased, and the fluid will be turned and directed to the secondary turbine which latter will exhaust the fluid in the same direction of rotation as the primary impeller. The cooperating elements such as impellers, turbines and guide members are so arranged, rotated and shaped, that no preceding element can crowd or underfeed the next element.

Accordingly, one of the principal objects of the present invention is to provide in a hydraulic transmission of the above type, a novel construction wherein abrupt changes in the course of the Working fluid are avoided, thus materially decreasing losses in eiciency due to the generation of large amounts of heat and undesirable decreases in the velocity of the fluid.

Another object is to provide a novel hydraulic transmission construction embodying primary and secondary impellers together with primary and secondary turbines, which are so constituted that the secondary turbine and impeller cooperate to direct, guide and increase the fluid capacity without abrupt or sudden changes in the direction of flow, and where the fluid exhaust from the secondary turbine is moving in the same direction as the primary impeller.

Still another object resides in constructing and arranging the impeller, turbine and fluid guiding members so that overfeeding of succeeding members and losses in the velocity of the working fluid are prevented.

Another object is to provide a novel controlling mechanism for a hydraulic transmission of the above type which is highly eflicient in its operation, and is well adapted, but not limited for use with automotive Vehicles.

A further object comprehends a construction which avoids the use of costly and separate mechanical clutches by controlling the eectiveness of the uid working circuit in a novel manner.

Still another object resides in the provision of a single control lever which is effective in its operation to disconnect the driven shaft from any driving member, connect the driven shaft to the turbine drive for forward or reverse, control the hydraulic transmission to release the same for free rotation and connect the driving shaft directly to the driven shaft for direct drive.

A fufhEl" 01056013 iS to provide a novel arrangement for combining the torque derived from the primary and secondary turbines of the transmission, thus resulting in a material vincrease in power.

A still further object resides in the-provision of a novel cooling arrangement for the parts of the transmission, so arranged as to avoid the pocketmg of heat within the interior of the iluid circuit.

Still another object is to provide cavities, which eiasos 3 would otherwise accumulate surplus working fluid, with fillers or heat transfer members which communicate with the exterior of the hydraulic circuit and eiciently convey heat generated and stored in the fluid to the outside atmosphere.

A still further object is to provide a transmission of the labove type which includesrelativelyj few parts which are constructed and arranged as' to present an unusually compact, readily controllable and highly elcient structure.

Other objects and novel features of the invention will appear more fully hereinafter `frorrra consideration of the followingsdetailedV descrip-Y tion when taken in connectioniwith'theaccom-.- panying drawings illustrating one form of the invention. It is to be expressly understood, how.- ever, that the drawings are utilized for purposes of illustration only and are not to be taken .asa` definition of the limits of the invention, reference being had for this purpose vto the appended claims.

In the drawings, .wherein similar reference characters refer to similar parts throughout the several views;

Fig. 1 is a side view partly in section of afluid transmission embodying ythe `principles .of the present invention; y

Fig.2 is a fragmentary sectional view of theA` transmission taken substantially along line y2-2 of Fig. Y1;

Fig. 3 is a sectional viewV taken substantially alongline 3-3 vof Fig. land illustrates the ring valve for controlling the fluid circuit;

Fig. 4 is a side view partlyin .section of the novel uid guide member vand Aillustrates certain of the construction for efficiently cooling the interior of the hydraulic unit.;

Fig. 5 is a schematic side view of certain ofthe novelcontrolling mechanism employed in connection withthe unit of Fig. 1.;

Fig. 6 is a partial sectional view taken substantially along line 6 6 of Fig. 1 and illustrates the cooperative relationship between the secondary impeller and the secondary turbine.;

Fig. 7 is a side view of the sleeve for controlling` the operation of the ring valve, and.

Fig. 8 is a sectional .view taken substantially along line 8--8 Vof Fig. '7.

Referring more particularly to Fig., 1, the novel hydraulic power transmission of :the present invention is illustrated therein as :comprising a fluid unit II! .arranged to .driVably-connect `driving and driven shafts I2 and .I4-respectively, the :driving shaft being rotatably supported -in main casing I 6 by means of bearings I8, and the driven shaft being mounted in a selector clutchhousing V'2U through bearing 22. As shown, the driving shaft I2 is splined at 24 to an intermediate impeller and control shaft 26 which is .projected through the unit I0 and is rotatablysupported within the hollow driven shaft I4 in any suitable manner. As will appear more fully hereinafter, the shaft 26 is employed not only for driving the impellers of the unit IU, but also for securing desirable controlling features at the will of the operator.

One of the novel features of the present invention resides in the construction and arrangement of the iluid unit I0 which provides a dual impeller and turbine structure arranged to avoid abrupt and sudden changesfin the direction of the flow of the working fluid and to dissipate any heat generated in the latter in ahighly effectivemanner. As shown, the unit Ill includes a primary impeller 28 which is suitablysplined at 30 to the intermediate shaft 26, and is provided with a plurality of spaced-apart outwardly extending vanes or blades 32 which are gradually curved in a direction opposite to direction of rotation of the primary impeller, see Fig. 2. A secondary impeller 34 is positioned radially outwardly of the primary impeller 28 and is provided with a pluralityv ofblades ,orvaneswhich are gradually curved in a direction opposite to the direction of rotation of the secondary impeller, see Fig. 2.

Means are provided for positively driving the secondaryimpeller 34 from the primary impeller 28"and in'a direction opposite to the direction offzrotation of the-latter. As shown, such means includes.afreversin'g` gearing comprising an impeller'ring gear .38 "carried by the primary impeller.28, a plurality of pinions 4U, and a driving 'gear '42; the latter being connected with the secondaryfimpeller 34 through a toothed clutch 44. Pinions 40 are carried 'by a pinion carrier 46 which vvis splined rat 43 to the rear disk50 -of a normally stationary4 fluid guide member 52, the

said disk 50 being provided with a hub portion .for

rotatablymounting the driving gear 42. In this manner, see Figs. land 2, .it will be readily seen that the `secondary impeller 34 will be rotated 'in a clockwise direction, as denoted by the arrows A, upon counterclockwise rotation of the primary impeller 28,- as indicated .byv the arrowB, when viewed from the direction of the'arrow Rin Fig. .1. Such an Y arrangement insures an outward -radial .flow of working rfluid .followed by a lateral ow Vfrom vthe side of' the .secondary impeller 34, it being noted from Fig. i1, that the construction of the latter is such that the -directionof the flow of .fluid in the fluid `working circuit, as shown by the arrows 54, is gradually changed .from an outward radial Aflow to a lateral flow.

In order to transmit torque from the primary and'secondary impellers 28 and 34 respectively, to thedriven shaft I4 through the iluid circulatn ing in the path 54, the present Iinvention provides a novel turbine construction which cooperates with vthe impellers inv a highly efcient manner. As shown, such construction .includes a primary turbine 56 which is xed in any suitable manner -toa primary turbinesleeve 58 which is rotatably supported on the intermediate shaft 26; A plurality Yof vanes or blades 60,' are carried by the primary turbine 45t, and these are spaced apart and generally curved .inthe same direction as the-blades 32 lof the primary impeller 28. From this arrangement, itwill beV appreciated from Fig; 2, that with the primary-impeller v23 rotating in the direction of the arrow B, the fluid traveling from theY primaryiimpeller blades 32 to the primar-y turbine `blades 60 will cause the primary turbine 56 rto rotate in the same direction as shownl by the arrow C. It will also-.be noted from Fig. 2 tha-t the fluid exhausting vfrom the primaryturbme 55 takes the direction as shown by the arrows D which is `opposite to thedirection-of lrotation of the primary turbine 56.`

Since the secondary impeller 34 .is geared to rotate in the `opposite direction from that of the primary impeller 28, it will Ibe clear that the direction of .rotation -ofthe Yformer will be the same as thedirection off travel of the fluid as. it is exhaustedA from the primary turbine 5.5., see the arrows A and D.. Thus the fluid will be iiowling in a direction such as to assist the rotation of thesecondary impeller .34 as the fluid strikes the concave sides ofthe vanes 36. Thereafter, the fluid continues to ow outwardly, under the influence offcentrifugal "force, lthe llid velo'c'it'y is increased over its initial velocity, and its direction is gradually changed so as to bw laterally, as heretofore described.

For the purpose of completing the fluid circuit and establishing ythe toroidal fluid path 54 characteristic of hydraulic devices of the general type to which the invention appertains, the invention provides a novel secondary turbine structure B2 which cooperates with the normally stationary guide member 52 and functions to deliver the fluid to the primary impeller 2B without any sudden changes in the direction of flow and Without overfeeding the latter. In the form of the invention illustrated, the secondary turbine 62 includes a plurality of vanes or blades 64 which are so curved as to cause the turbine to move in a clockwise direction, sce arrow E of Fig. 6, when Viewed at the top of the unit in the direction of the arrow R. Thus the secondary turbine rotates in the same direction as the secondary impeller.

The fluid exhausting from the secondary impeller and the secondary turbine on the other hand will be moving in an opposite direction, see arrows F of Fig. 6, and such uid is received within the space 80 defined by the rear disk 50 and a forward disk 53 of the member 52 and nally delivered to the primary impeller 2B by way of a plurality of hollow guide vanes carried by member 52. Previously the latter vanes are gently curved in the direction of the fluid flow, as the fluid is exhausted from the secondary turbine, so that the direction of ilow of the iiuid as it is delivered to the vanes 32 of the primary impeller 28 will Ibe the same as the direction of rotation of the latter.

As shown, the secondary turbine 62 is carried by the casing of the unit I0, such casing including a forward section '|2 which is rotatably mounted upon a bearing 14, and a rear section 'I6 to which a secondary turbine sleeve 18 is secured in any suitable manner. The turbine 62 is mounted on the forward section 12, as by means of a plurality of screws 80, and both sections of the casing are secured together by a plurality of bolts 82. As will be readily seen from Fig. 1, the rear section 13 is formed to provide a pair of annular spaced apart rings 84 and 86 for rotatably supporting the secondary impeller 34.

From the foregoing description it will be seen that the guide member 52 not only serves to guide the working fluid in its travel from the secondary turbine to the primary impeller, but also functions as a support for the reversing gear carrier 46. In addition to these desirable functions, the member 52 also provides a novel construction for effectively dissipating heat which may be generated due to the circulation of the working fluid. More particularly, the guide member 52 includes a main sleeve 88 which surrounds the intermediate shaft 26 and is rotatably mounted thereon in any 'suitable manner. The forward portion of the sleeve 88 is provided with a series of gear teeth 30 with which a gear brake 3-2, splined at 93 to a stationary arm 94, cooperates in maintaining the member 52 stationary or allowing it to be released in accordance with longitudinal movement of the shaft 26. For example in the position shown in Fig. 1, the sleeve 88 and the member 52 are held stationary by cooperation of the parts Sii, 82 and 94. Upon movement of the shaft 26 to the left, however, the brake 92 will be moved, through an actuating flange 96 xed to the shaft 26, to disengage the teeth 90. Thereupon-the sleeve 88 and member 52 will be released. The conditions under which this control 6 is effected will be referred to more fully herein# after.

Surrounding the main sleeve 88 is a secondary sleeve 38 which is formed to provide a Ventilating space |00 between the sleeves. At its rear end, the sleeve 98 is provided with a flanged portion |02 having a plurality of openings |051 therein, such anged portion being connected to a hub element |06 as by means of an annular ring |08. The rear disk 50 is connected at its periphery with a disk |I0, these elements being spaced slightly from each other to define a Ventilating chamber |I2 which communicates with the chamber |00 by way of a plurality of tubes I|3, extending through hollow vanes 10, opposite ends of the tubes being respectively supported by the disk H0, and the hub element |06, as clearly shown in Figs. 1 and 3. From this construction, it will be readily ascertained that free communication is established between the Ventilating chamber I2, located within the toroidal path 54 gf tle working fluid, and the Ventilating cham- In order to provide for additional ventilation and cooling of the parts, the guiding member 52 also includes a Ventilating space I|4 defined by a disk I I6 which is spaced from but connected at its periphery to the forward disk 68. Such space I I4 also communicates with the space |00 as will be clear from an inspection of Figs. 1 and 4. The latter space is in constant communication with a bladed exhaust ring ||8 which connects the space |00 and the Ventilating spaces |I2 and ||4 communicating therewith, with the atmosphere through the exhaust ring I I8.

In the form of the invention illustrated, the forward casing section 12 is provided with a plurality of Ventilating vanes |20 having a cover |22 arranged to direct a iiow of cooling air past the exhaust ring I I8, between the vanes |20 and outwardly at the periphery of the unit I0 adjacent fins |24 on the exterior of the forward casing section '|2. The cooling air passing by the exhaust ring IIB materially assists the ventilation of the chambers connected with such ring, the action in this respect being in the nature of an ejector.

IIn like manner, the rear casing section I0 is provided with a plurality of Ventilating vanes |26 having a cover |28, while the section 'I6 at its periphery, has associated therewith, a plurality of cooling fins |30. As will be readily seen from Fig. 1, the unit I0 is housed within a stationary casing |32 having forward and rear sections |34 and |36 which are connected together by a series of bolts |38. A yplurality of inlet openings |40 are provided for the intake of cooling air, the latter being exhausted through an ejector opening |42. Thus, in the case of an automotive Vehicle installation, when the vehicle is moving forward, cool fresh air is drawn in through air intake openings |40 in the stationary casing |32 and the rotation `of the fluid unit I0 draws in the air at its hub and exhausts the air at its periphery. Furthermore, the forward movement of the vehicle creates an air stream which passes over the air exhaust opening |42 in the stationary casing |32 to aid in exhausting the air from the casing. Thus, a continuous circulation of cool fresh air is passed over and around the fluid unit I0 in order to effectively cool the latter.

In order to further assist in the ventilation and cooling of the working parts, the secondary turbine 62 is formed with an annular recess |44 which is adapted to communicate with the 2go-zogenaatmosphere by means of afpluralityyofopenings The |46 spaced about the periphery thereof. secondary impeller 34 isfprovided with a, somewhat similar Ventilating arrangement, the samev comprising'an annular filler tank |48 provided with a plurality of openings |50, see particularly position shown in Fig. .1, the valvev |52 is retracted-v and hence offers no o-bstruction to the freeiiow of the working fluid in the circuit 54. projected to the right, as viewed-in lthis figure, however, the valve |52 contacts the disk ||0 and completely interrupts the ow of the working.

uid. Under these conditions, thetransmission of torque from the impellers 28- andf`34 to the turbines 56 and 62 is likewise completely interrupted and the driven members lare thus effectively disconnected from the driving. members.

A novel arrangement is providedv for controlling thefmovementsV of the-valve |52V and preferably the .construction is such that the movements may becoordi'nated with certain of the conventional controlling elementsvof an automotive vehicle. More" particularly, valve controllingv sleeve |56 having a plurality of longitudinally.. extending fingers |51, is positioned within thefspace between theY sleeves l88 and 98 and arranged to be shifted in said space by means of a-yoke or collar |58, secured to the sleeve |56 as byl a pin |59, a. suitable slot V|60 being provided in the sleeve 98 to accommodate the pin duringshifting movement of the yoke |58 to the right, as .viewed in Fig. l. As shown, the control ring valve |52 is provided lwith a plurality of hollowY spokes |`6| whichc-ontain suitable pins |62, the ends of which project into openings |63 provided in the ends of the fingers |51. In this manner, axial movements of the sleeve |56 will causecorresponding. axial movements ofthe ringvalve |52, it beingpointed out that suitableslots |64, Fig. 4,

are provided in thesleeve 98 for accommodating such movements of the pins |62. Preferably, the chamber |54 is filled with a plurality of .cavity llersor tanks |66 which. communicate with the openings |04; this construction. ir1;--;uring ventilation and. cooling of the interior of the ring valve |52, as well as avoiding accumulation of surplus fluid in chamber |54. l

In order to control the movementszofth'e ring valve |52, a lever |68'pivoted' at |10' to astationary bracket |12, has one end g |14 thereof associated with the yoke |58,xand thejother'end |16 thereof operativelyv connected with certain-of the automotive vehiclev control elements. As' shown, Fig. 5, such elements includean acce1er= ator pedal |18 pivotally-mounted'at- |80`to a suit'- able bracket |82 and bein'g'operativel-y connected to a carburetor throttle rodr|84 b'yiineahs o'fa bell crank lever |86'. Preferably'aspring loaded connection |88 is interposedbetween. the rod |84 and one arm of the lever |86 for a purpose which will appear more fully hereinafter. An operating link or armV |90 is pivotedto theupperfend |16 of the lever. l 68 and .has its oppcsiteends-:pivctally connected with bell. crank 'levers |'92iand |94. Asfshown, the-lever* I 924s arrangedrtoabe-operated When in afclockwise direction about .itsfpivotal-mcunb ing |96, as by a vertically movablerod- |98, W-hile thelever |94 is mounted for movement in ja similar manner by shifting of ay rod 200. The accelerator pedal |18 lis coordinated withthe rods |98 and 200 in such a manner that operation thereof in opposite directions from the position indicated will serve to selectively shift the said rods downwardly. Thus inthe event the pedal` |18 is rocked to the-position M, rod 200 will be shifted to cause counterclockwisemovement of thej lever |68 about its pivot in order to shift the valve=|52and completely interrupt the circulationof fluid in thev path 54 as heretofore described. On the other hand, should the Vpedal |18 be rocked past the full throttle position N to the position` O, tljlerod |98 will affect'mo'v'ement of the leverV |68 in the same direction.Y It will be understood that movement of the pedal |18 from position N to position O is permitted by reasonof the spring loaded connection |88 'interposed-in the carburetor throttle linkage. It is also desired to point out that the connections between the rod |938 and the-lever |68 are preferably such that the valve |52 will only partially interrupt the fluid circulation in the .path 54 when the pedal |18 reaches the position O. The advantages of this arrangement will appear'more fully hereinafter. Y y

Preferably, the lever |68" is valso operatively' connected to the vehicle brake operating pedal 282 so'that upon application -of the vehicle brakes,v the circulation of uid inthe path 54 will'be interrupted in order to disconnect thev impeller and turbine members. Asshown, such connec-v tion includes an arm 204 secured to the `brake pedal 202 and cooperating with anmarm of the lever |94 through a spring 206. Thus, as the pedal 282 is pivoted about the pivotal mounting 208 therefor, to apply the vehicle brakes through anyosuitable linkage 2| 0, the arm 204'will rock the lever |94 in a clockwise direction inorderto shift the link and correspondingly close the valve |52 through theflever |68 and the connections heretofore referred to. It will be -clear that the use of the spring 206 allows complete freedom of movement of the pedal 202 for properv and effective brake operation. Thus the pedal 202 nasa primary functionof closing` the ringvalve |52 and arrestingthe fluid circulation' in order to effectively disconnect the driving and driven shafts.. and thus neutralize the transmission. Pedal202 also has a secondary function of applying the brakes to stop the driven shaft from rotating after motion of the vehicle is arrested.

It will be readily understood from the foregoing that during operation of the fluid unit I0 with the establishment of the fluidv working circuit-54, the primary turbine sleeve -58 and the secondary turbine sleeve 18 will be rotating in opposite directions. For example and viewing theseparts from the front'offthe unit.' in the direction of the arrow H, shaft 26 and sleeve 58 will be vrotating clockwise while sleevela will be rotating countercloc'kwise. In order'to `con'ibir'ie the torque outputs fromthe sleeves' 58 and 18 and hencethe outputs ofthe primary and secondary turbines 56 and` 62 respectively, a novel arrangement is contemplated. More particularly, and as shownin Fig.- 1, su'c'h an arrangement includ-es a reversing gearing constituting a' transfer mechanism 2|2. Such mechanism includes a drive ring 2 I4 which splined Vat 2|6 to-v the 'secondary turbine sleeve 18, andy which is connected toar secondary transfer gear 2|8 throughlal' oneway.y clutch 2l-9, andv carries: a

cover member 220 provided with clutch teeth 222. A plurality of pinions 224 mesh with the gear 218, and the former are also arranged to mesh with a primary transfer gear 226 which is splined at 228 to the primary turbine sleeve 58. A pinion carrier 230 is provided for supporting the pinions 224 and such carrier, in the position shown in Fig. 1, is held stationary in the following manner. A locking and reversing sleeve 23| is arranged to be shiftable on the primary turbine sleeve 58 and is provided at its forward end with clutch teeth 232 to engage corresponding clutch teeth 234 formed on the pinion carrier 230. With the latter teeth in engagement, clutch teeth 236 formed on the sleeve 231 are engaged with similar clutch teeth of an anchor member 240 secured in any suitable manner to the stationary v transfer housing 242. Thus with the pinion carrier 238 held stationary, it will be readily seen that the torque of the secondary turbine is combined with that of the primary turbine through the sleeve 18, drive ring 214, one-way clutch 219, secondary transfer gear 218, pinions 224 and primary transfer gear 226, it being recalled that the latter is splined to and thus drivably connected with the primary turbine sleeve 58. Thus the combined tordues are delivered to the sleeve 58 for subsequent use in driving the -driven shaft I4.

A further important feature of the invention resides in the provision of a novel controlling mechanism for controlling the action of the uid unit 18 in certain respects, and for securing various driving connections between driving shaft 12,

the primary and secondary turbine sleeves 58 and 18 respectively, and the driven shaft 14, all at the will of the operator. More particularly, and as shown in Fig. 1, the selector housing 20 is provided with a forward shift rail 244 and a reverse shift rail 246, these rails being spaced apart and lying in a horizontal plane. The forward shift rail 244 slideably carries a shifting yfork 248 which is operatively connected with a master yoke 258 in such a manner as to shift the latter to the left, as Viewed in Fig. 1, in order t0 selectively establish the desired driving connections. In a similar manner, a reverse shifting fork 252 is slideable along the reverse shift rail 246 in order to control the position of the sleeve 23|. A selector control lever 254 is universally mounted in the casing 20 and provided with a lower end 256 for selective engagement with either of the shifting forks 248 or 252 for effecting the aforesaid shifting movements. Preferably, a spring 258 is associated with the lever 254 in order to resiliently maintain the latter in a posi- -tion where the shifting fork 248 is engaged by the lower end 256 thereof. If desired,each of the shifting forks may be provided with conve-ntional ball detents 268 which are engageable with suitable notches 262 formed in the shift rails in order to yieldingly maintain the said forks in their adjusted positions. While not illustrated, it is contemplated that a shifting lever mounted beneath the steering wheel of the vehicle will be lconnected through a suitable linkage with the lever 254 in order to control the operation of the latter.

For establishing the various driving connections, the master yoke is provided with a plurality of gear type Clutches and is also splined at 264 to the driven shaft 14 so as to be axially movable with respect to the latter. More particularly, the aforesaid clutches comprise a reverse clutch member 266, a turbine clutch member 268, and a direct drive clutch member 210|,

the latter being rmly secured to the intermediate shaft 26 by a pin 212 and being provided with a yoke or collar 214 for receiving the end of an actuating pin 216 carried by the master yoke 250. Due to this latter construction, it will be readily seen that the clutch member 218 and the intermediate shaft 26 to which it is secured, are moved axially in accordance with all shifting movements of the master yoke 258. The reverse clutch member 266 is adapted to cooperate with a complementary reverse clutch member 218 carried by the sleeve 231, while the clutch members 268 and 216 respectively engage a complementary turbine clutch member 288 and a direct drive clutch member 282. The latter two clutch members are formed on a clutch collar 284 which is secured to the primary turbine sleeve 58 in any suitable manner.

In operation, and assuming that the fluid unit 10 has been filled with sufcient fluid to constitute the working circuit 54 when the unit is in operation, the selector lever 254 is moved to the neutral position L, and the engine is started. This causes rotation of the shafts 12 and 26 and the primary impeller 28 connected therewith, all of these parts rotating in a counterclockwise direction when viewed in the direction of the arrow R, see Figs. 1 and 2. Fluid exhausting from the primary impeller will take the general direction as shown by the arrows D of Fig. 2 and such fluid will strike the blades 60 of the primary turbine 56 and cause counterclockwise rotation of latter as indicated by the arrow C. Since the secondary impeller 34 is geared through the gearing 38, 48 and 42 to the primary impeller 28 so as to be driven in a clockwise direction, see arrows A of Fig. 2, and the fluid exhausting from the primary turbine 56 is also moving in a clockwise direction, it will be readily understood that such fluid assists in rotating the secondary impeller when it strikes the curved vanes 3B of the latter. Under the continued inuence of centrifugal force, the fluid moves to the inside periphery of the secondary impeller 34 where its initial velocity is increased and the uid is turned and directed axially against the vanes 64 of the secondary turbine 62, see Fig. 6. The action of the fluid flowing axially through the secondary turbine will rotate it in the same direction as the secondary impeller, as indicated by the arrow E of Fig. 6, and the fluid exhausting therefrom will be generally directed in a counterclockwise direction as shown by the arrows F, which is the direction of rotation of the primary impeller 28. Thereafter the fluid working circuit is completed by the flow of the fluid radially inwardly through the space 66 of the guide member 52, and past the vanes 10 which as heretofore stated, are gently curved to maintain the counterclockwise movement of the fluid and to deliver the latter to the primary impeller 28 which, it will be recalled, is also rotating in a counterclockwise direction, see arrow B. From the foregoing, it is seen that the path of the duid follows a free ow with no abrupt or sudden changes of direction which would otherwise create turbulence and the generation of heat and would result in a lowering of the efficiency of the converter. Moreover the arrangement is such that overfeeding or underfeeding of any succeeding element of the unit 18 is prevented. y

Under certain conditions, and especially when initially establishing the fluid working circuit 54 following a condition of rest, there may be some tendency for fluid to accumulate within the :agar-agace v@21,1 space housing the reversing gearing 38, 540 and 42. For thev purpose of expelling such iiuid` and returning it to the working' circuit, a plurality of vane members 296 are attached tothe gear 42 and arranged toY direct the uid axially'outwardly into the space 66.

It is well known that during the operation of torque converters of the uid type, a considerable amount of heat is generated in the working uid and parts associated therewith, and various arrangements have been proposed in an effort to dissipate such heat. The interior cooling and Ventilatingv means of the present invention, heretofore described in detail provides a highly emcient construction for eifecting such heat dissipation. For example, andreferring to Fig. 4, it will be noted that the Ventilating spaces ||2 and I |4 are arranged on opposite sides of one leg of the fluid working circuit 54 and these `spaces communicate with the exhaust ring ||8 by way of the annular chamber |00. Additional and eicient cooling means are provided by the vaned casing parts 12 and 16, the ns |24 and |30, and the parts |44, |48 and |66. It is also pointed out that the fluid unit is rotatably mounted in the stationary casing |32 and during operation, draws in cool fresh air through openings |40. and exhausts the air through the exhaust port |42. Hence, the entire uid-unit IU is pro-vided with a constant circulation of cool fresh air. It will be noted from Fig. 4 that the uid guide member 52, while comprising a plurality of separate parts, nevertheless is so constituted as to provide a unitary assembly for association with the impeller and turbine members. Thus, all'of the constituent elements are welded together in the manner shown in Fig. 4, it being understood that the valve |52 is positioned as shown in Fig. 1 prior to the welding operation.

During operation of the fluid unit I0, as above set forth, the torques derived from the secondary turbine |52A and the primary turbine 56 are combined in the transfer gearing 212 and delivered to the primary turbine sleeve 58. Thus this sleeve and the clutch member 282 will be rotated in a counterclockwise direction when the unit is viewed from the direction indicated by the arrow R, Fig. 1. This is the same direction of rotation as the driving' shaft |2 and the intermediate shaft 26. Under these conditions, the pinion carrier 238 of the transfer gearing 2|2, is maintained stationary by means of the clutch 236 on the sleeve 23| which engages the stationary part 240. With the lunit functioning in this manner, the fork 248 on the forward shifting rail 244 may be moved for eiecting various forward driving conditions.

In the event. that it is desired to establish' 'a forward drive through the torque vconverter in order to utilize the torques derived from the primary and secondary turbines 56 and 62 respectively, it is rst necessary to vinterrupt the transmission of torque between :the impellers and the turbines through operation .of ring valve |52. 'Ihis is eiected by rocking theaccelerator pedal |18 from the neutral position illustrated in. Fig. 5, to the position M in order'to depress the rod 28|) and shift the valve |52 to the right as viewed in Fig. 1, to interrupt Vthe ow of the luidin the working circuit54. As understood from the previous description, such .movement of the valve |52 is accomplished through the bellcrank lever |84, link; |98, lever |68, collar |58, sleeve |56 and the connection |62 between the latter sleeve and the ring valve |52. Preferably, a centering these parts ceases.

or 'neutralizing' spring, notY` shown, -is associated with "the leverV |68 in order to resiliently maintain the same and the valve |52 in the neutral positions illustrated in Fig. l, and it is understood that when the ring valve is operated as above set forth, the lever |88 is moved in a counterclockwise direction about its pivotal mounting |10 and against thel tension of the centering spring. However, the centering or neutralizing spring keeps the valve |52 in an open position and returns the valve to the open, neutral position shown in Fig. l after being actuated by pedals |18 orv 202.

Following the operation of the ring valve |52, the'turbine members 56 and`62I will be electively disconnected from the impeller members 28 land 34 so that all transmission of torque between When this condition occurs, the operator moves the selector lever 254 to the positions asshown in Fig. l, in order to bring the turbine clutch members 258 and 283 into engagement. Thereafter, the accelerator pedal |18 is moved to its normal position or beyond for opening the carburetor throttle, and the ring valve |52 is returned to the position indicated in Fig..1. At this stage, the now of the working fluid in the toroidal path 54 is re-established and the' drive Vfrom the fluid unit will be transmitted from the primary turbine sleeve 58 to the driven shaft I4 by way of the clutch elements. 288 and 258, and the master ycke250 which is splined to the driven shaft I4 at 264.

It will be understood that during movement of the master yoke 250 to. the left as viewed in Fig. 1. to establish the turbine drive, intermediate shaft 26 will also be. moved a slight distance to the left through the connection between the master yoke 250- and the clutch collar 214 which is affixed to thevshaft26. When this movement occurs the brake 9.2.is also moved a slight distance to the left buty insuiiicient to effect disengagement between the stationary arm 94 and the teeth 98. formed on the sleeve 88 of the fluid guide member 52. Thus, the latter member will remain in a stationary condition.

In the event that the selector lever 254 is thereafter moved vto the position T, following interruption of the fluid working circuit 54 by closing of thering valve |52 as above set forth, the turbine drive between the clutch members 280 and 268 is .maintained However, the intermediate shaft 26 is moved a sufficient distance to the left as to effect disengagement between theiteeth and the brake 92. With the uid guide member52 thus released from its stationary condition, it will be readily understood that the reversing pinion carrier 46 carried by the rear ydisk 50 of such member will be free for rotation with Ythe guide 'member 52, and under these conditions, the reversing gearing connecting the primary impeller 28 and the secondary impeller 34 will be effectively disconnected. This allows the rimpellers and turbine members to follow the directionof rotation of the fluid in the unit I0, whichas heretofore stated, is being iniiuenced to rotate in a counterclockwise direction. The secondary turbine 62 and the casing comprising sections 12 and 16, hence rotate in the same direction as the primary turbine 56v this being permitted by reason of the onewaygor overrunningclutch 2|9. Thereafter, it is onlynecessary to. move the ring valve |52 to open position .in order to re-establish the Huid workingi circuit 54 andobtain the drive solely through the primary impeller 28 vand the primary 13 turbine 56, which latter is connected with the primary turbine sleeve 58 which is clutched to the driven shaft I4.

In order to establish a direct drive between the driving shaft I2 and the driven shaft I4, thus isolating the fluid unit l, the ring valve |52 is moved to its closed position and the selector lever 255 is then moved to the position indicated at V in Fig. l. This action causes movement of the master yoke 250 and the direct drive clutch 270 a sufficient distance to the left as to bring the teeth of the latter clutch into engagement with the complementary direct drive clutch 282. Since the clutch member 234 is maintained in driving relationship with the master yoke 255 through the engaged clutch members 285 and 258, it will be readily seen that the direct drive may be established between the driving and driven shafts. Thereafter, it is only necessary to move the accelerator pedal IIS in a conventional manner in order to control the operation of the vehicle in the direct drive.

In establishing a reverse drive, the ring valve |52 is first moved to its closed position and the selector lever 254 is thereafter moved to pick up reverse shifting fork 252. Shifting of the lever 254 to the position K, then establishes the reverse gear relation in the following manner. Upon movement of the reverse shift rail 252 to the right, as viewed in Fig. l, sleeve 23| will also be moved to the right. This causes a declutching action between the clutch members 232, 234 as well as a de-clutching action at the clutch 236. The clutch member 232 will then be shifted into engagement with the clutch member 222 of the cover 22B and the sleeve 23| will then be rotated in a clockwise direction by reason of the fact that the cover 22|) is connected to the secondary impeller sleeve 18. A slight continuing movement of the sleeve 23| will then bring the reversing clutch members 256 and 2718 into engagement in order to elfect a reverse drive of the driven shaft I4 through the master yoke 250. Here again, the fluid working circuit 54 is re-established by opening of the valve |52 through movement of the accelerator pedal in a forward direction from the position M. It will be understood, of course, that the reverse gear relation is established after the lever 254 has been returned to the neutral position L, so that the fluid guide member 52 is locked in a stationary condition through the clutch 52 and the cooperation of the latter with the clutch teeth 90 and 93.

From the foregoing, it will be readily perceived that the ring valve |52 functions in a highly eicient manner in order to interrupt the transmission of torque between the impeller and the turbine members. Thus the necessity of utilizing a separate and costly mechanical clutch arrangement is completely avoided.

In the event that the vehicle is being driven by the fluid unit I0, and the load imposed upon the engine has decreased its speed and torque, the following operation is followed in the event that a sudden and quick acceleration of the vehicle is desired. The accelerator pedal |12 is moved beyond its full throttle position N to the position O as indicated in Fig. 5. This action, as heretofore stated, is permitted by reason of the inclusion of the spring loaded connection |83 in the linkage between the accelerator pedal and the carburetor throttle. During movement of the accelerator pedal as thus indicated, the rod |98-is moved downwardly in order to effect counter- 14 clockwise movement of the lever |68 about its pivotal mounting This action causes a partial closure of the ring valve |52 which will relieve the engine of a portion of its fluid load in order to permit an increase in its rate of speed. As soon as this occurs, the velocity of the fluid in the working circuit 54 will increase and the torque delivered by the fluid unit will be also increased. Thus, with this arrangement, a sudden and quick acceleration of the vehicle may be obtained by merely moving the accelerator pedal beyond its normal full throttle position. Upon return of the accelerator |18 to its throttle operable position, the valve neutralizing spring previously described as being associated with the lever |68, provides power means to return the valve |52 to a neutral position, thus again permitting a free ilow of the huid in the circuit 54.

The present invention thus provides a novel hydraulic torque converter combined with a novel control system which is arranged to provide a highly advantageous construction. For 'example, one of the important features resides in the use of the novel fluid guiding member 52 which is formed to not only guide the fluid during its travel, but also to serve as an efficient means for the dissipation of heat generated interiorly of the converter. A further feature resides in the construction and cooperation of the impeller and turbine members, it being clear from the foregoing description, that these members are so arranged that no sudden or abrupt changes in the direction of the fluid flow occurs, and overfeeding or underfeeding of each succeeding unit is completely avoided.

In addition to the above, the control system is such that the torques of the primary as well as the secondary turbines are combined in order to increase the power output of the converter. Also, the drive selector construction provides a simplified and efiicient manner of selecting and establishing the various driving conditions in cooperation with the iluid control valve, which latter avoids the necessity of complicated and costly mechanical clutches.

It will be readily understood that while one embodiment of the invention has been shown and described herein, various modiiications may be resorted to without departing from the spirit of the invention. For example, the construction is well adapted for a variety of uses other than for installation in an automotive vehicle. Also, the guide vanes 1|) of the guide member l52 may be extended to the secondary turbine 62 if desired, and by changing the profile of such vanes, the fluid guide member may be employed as a conventional reactionary member. In addition, cooling air may be forced through the Ventilating space |50 and the cooling passages connected therewith. Those skilled in the art will perceive various other modifications and changes without departing from the essence of the invention. Reference will therefore be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. A hydraulic variable speed power transmission comprising a casing containing a working fluid, a rotatable bladed primary impeller for directing said fluid radially outwardly, a radially extending bladed primary turbine for receiving the radially directed fluid, a bladed rotatable secondary impeller arranged to receive the huid exhausted from the primary turbine and to exhaust said fluid in an axial direction, means for opposite to that of the former, a rotatable bladed seconda-ry turbine Vfor receiving the. fluid exhausted from thesecondary impeller, and a fluid guide member for receiving the fluid from the secondary turbine and for returning said fluid vto the primary impeller.

2. A hydraulic variable speed power -transmission comprising a casing containing a working i fluid, a rotatable bladed primary impeller for directing said fluid radially outwardly, a radially extending bladed primary turbine for receiving the radially directed fluid, a bladed rotatable secondary impeller arranged to receive the iluid exhausted from the primary turbine,4 increasev its velocity and to exhaust said fluid in an axialfdirection, means connected with the primary impeller for rotating the secondary impeller 'in a direction opposite to that of the primary impeller, a rotatable bladed secondary turbine for receiving the fluid exhausted from the secondary impeller, and a fluid guide member for receiving the iiuid from the secondary turbine and for returning said fluid to the primary impeller.

3. :A hydraulic variable speed transmission of the c haractersetforth in claim 2, which comprises in addition, controlling means operable to cause rotation of all of said impellers and turbines inthe same direction.

4..YA hydraulic variable speed transmission of the character set forth in claim 2, which includes means for rotating one of said turbines and one of said impellers in either direction at the will of the operator.

5. A hydraulic variable speed transmission of the character set forth in claim 2,y wherein the means connected with the primary `impeller comprises a. ring gear connected with the secondary impeller, a second ring gear connected with the 1 Vprimary impeller, and a pinion carrier having a plurality of pinions operatively connecting said gears.

6. VA hydraulic variable speed transmission of the character set forth in claim 5,.which comprises in addition, means shiftable at the will of the operator for maintaining said carrier stationary, or for releasing it for free rotation.

'7. A hydraulic variable speed power transmission comprising a casing containing a working fluid, a rotatable bladed primary impeller 4for ydirecting said fluidradially outwardly, means for rotating the primary impeller in onedirection, a radially extending bladed. primaryturbine for receiving the radially directed fluid and rotatable in the vsame direction as the primary impeller, a bladed rotatable secondary impeller arranged to receive the fluid exhausted from the primary turbine and to exhaust said nuid in an axial direction, means connectedwith the primary` impeller for rotating the secondary impeller` in a direction opposite to that of the primary impeller, a rotatable bladed secondary turbine for receiving Athe, uid exhausted from the secondary limpeller, and a fluid guide member for receiving the fluid from the secondary turbine and for returning said fluid to the'primary i-mpeller.

8. A hydraulic variable speed power transmis- -sion'comprising acasing containing a working iiuid,v a rotatable'bladed primary impeller for directing said fluid radially outwardly, means for rotating theprimary impeller in one direction, a radially extending bladed primary turbine -for receiving the radially directed uid and rotatable -in the same direction.` as the primaryimpeller,

a bladed rotatable secondary impeller Y arranged to receive the fluid-exhaustedfrom the primary direction opposite to that of the primary impeller,

a'rotatable secondary turbine having a plurality vof bladesvarranged to receive the fluid exhausted -from the secondary impeller and to be rotated in the same direction as the secondary impeller, a fluid guide member for receiving the fluid from the secondaryk turbine, and a plurality of vanes carried by said guide. member for returning the fluid to the primary impeller and for directing the uid to flow in a path having the same direc- -tion as the Adirection of rotation of the primary impeller. .y

9. A fluid power transmission device, comprisingprimary and secondary impeller members. meansfor driveably connecting said members for rotating the .secondary impeller memberY in a direction opposite to that of the primary impeller member, primaryand secondary turbine members, a casing containing a working fluid, said members cooperating .with said fluid to direct .the latter in, aclosed circuit to transmit torque ,from the impeller members to the turbine members, a uid guide member between the secondary turbine and the primary impeller for receiving the fluid from the former and for delivering the fluidto the-latter.. and -means associated with the vguide member' for variably restricting the ow of fluid in said circuit.

l0. A-hydraulic variable speed power transmis- Ysion comprising lacasing containing a working fluid, a rotatable bladed primary impeller for v directing s aid fluid radially outwardly, means for rotating the primary impeller in one direction, a radiallyv extending bladed primary turbine for receiving the radially directed fluid and rotatable in thesamedirection as the primary impeller,

Aa bladed rotatablesecondary impeller arranged to receive the rfluid exhausted from the primary turbine and to exhaust said fluid in an axial direction, means connected with the primary impeller for rotating the secondary impeller in-a directionopposite. tothat of the primary impeller, a rotatable secondary turbine having a plurality of blades arranged to receive the fluid exhausted from the secondary impeller and to be rotated inthe samel direction as the secondary impeller,

.av primary trqlle. Output member connected with .with the primary torque output member or the secondary torque output member. 4 1,2. A hydraulic variable speed transmission of thelcharacter; set V.forth in claim 10 wherein the means for operatively connecting the output members comprisesa ring gear carried by one membenga second ring gear carried by the other memben and means. including a plurality 0f pinions operatively connecting said ring gears. '.i13.A,hydrau1ic variable speed transmission of the-characterset .forth in. .claim 12 which com plises in addition.- a carrier for said pinions, and

17 means shii'table at the will of the operator for maintaining said carrier stationary or for releasing it for free rotation.

14. In a fluid power transmission device, primary and secondary impeller members, means for driveably connecting said members for rotating the secondary impeller member in a direction opposite to that of the primary impeller member, primary and secondary turbine members, a casing containing a working fluid, said members cooperating with said fluid to direct the latter in a closed circuit to transmit torque from the impeller members to the turbine members, a fluid guide member between the secondary turbine and the primary impeller for re- "ceiving the fluid from the former and for deliver- `for driveably connecting said members for rotating the secondary impeller member in a direction opposite to that of the primary impeller member, prima-ry and secondary turbine members, a casing containing a working fluid, said members cooperating with said fluid to direct the latter in a closed circuit to transmit torque from the impellel1 members to the turbine members, a uid guide member between the secondary turbine'and the primary impeller for receiving the iiuid from the former and for delivering the uid tothe latter, means for normally maintaining said guide member stationary, a driving shaft, an intermediate shaft drivably connected with the driving shaft and with the primary impeller, a driven shaft, vmeans to combine the torques delivered by the turbines, and selectively operable means for connecting the driven shaft with said torque combining means or for connecting the driven shaft directly to said intermediate shaft while releasing said guide member for free rotation.

16. In a fluid power transmission device of the type having primary and secondary impellers and primary and secondary turbines, a casing containing a working uid, said members cooperating with said fluid to direct the latter in a closed circuit to transmit torque from the impeller members to the turbine members, a fluid guide member between the secondary turbine and the primary impeller for receiving the duid from the former andl for delivering the fluid to the latter, means including a brake for normally maintaining said guide member stationary, said brake being operable to release the guide member for free rotation, a driving shaft, an intermediate shaft dravably connected with the driving -shaft and with the primary impeller, a driven shaft, means to combine the torques delivered by the turbines, and selectively operable means for connecting the driven shaft with said torque combining means or for connecting the driven shaft directly to said intermediate shaft and for simultaneously operatingsaid brake to release the guide member. f

f the torque combining means ineective to combine the torques delivered by the turbines when the selectively operable means is moved to connect the driven shaft with the intermediate shaft.

18. A hydraulic variable speed power transmission comprising a casing containing a working fluid, a rotatable bladed primary impeller for directing said fluid radially outwardly, means for rotating the primary impeller in one direction, a radially extending bladed primary turbine for receiving the radially directed fluid and rotatable in the same direction as the primary impeller, a bladed rotatable secondary impeller arranged to receive the fluid exhausted from the primary turbine and to exhaust said fluid in an axial direction, means connected with the primary impeller for rotating the secondary impeller in a direction opposite to that of the primary impeller, a ro.- tatable secondary turbine having a plurality of 'blades arranged to receive the iiuid exhausted from the secondary impeller and to be rotated in the same direction as the secondary impeller, a. fluid guidevmember for receiving the fluid from the secondary turbine, means including a brake for normally maintaining said guide member stationary, said brake being operable to release the guide member for free rotation, a primary output member connected with the primary turbine, a secondary torque output member connected with the secondary turbine, means for operatively connecting said output members to combine the torques delivered by the turbines, said last named means comprising a reversing gearing having a normally stationary part, a driving shaft, an intermediate shaft drivably connected with the driving shaft and with the primary impeller, a driven shaft, and selectively operable means for releasing said normally stationary part and connecting the driven shaft to the secondary output member, or for connecting the driven shaft directly to said intermediatev shaft and for simultaneously operating said brake to release the guide member. 19. A fluid transmission comprising a casing, rotatable primary and secondary impeller members and rotatable primary and secondary turbine members within the casing for establishing a circulation of working iiuid in a closed path for the transmission of torque, and reversing gear means positioned within the closed path of the working fluid drivably connecting the primary and secondary impeller members for rotating the latter in a direction opposite to that of the former.

20. A fluid transmission comprising a casing having rotatable primary and secondary impeller members, rotatable primary and secondary turbine members, and a normally stationary fluid guide member'therein, all of said members cooperating with a working uid for setting -up a fluid working -circuit in a closed path for the transmission of torque, a part carried by the guide member extending within the closed path of the working fluid, and means including gearing having a gear element supported by said partl for drivably connecting the primary and secondary impellerl members.

21. A iiuid transmission comprising a casing having rotatable primary and secondary impeller members, rotatable primary and secondary turbine members, and a normally stationary fluid guide member therein, all of said members cooperating with a working iiuid for setting up a iuid working circuit in a closed toroidal path for the transmission of torque, means connected with the guide member andgforming a pair of annular 19 'Ventilating chambers respectively." positioned' on opposite' sidesfoioneleg ofi'the uidfworking circuitand: means to connect said. chambers. to the atmosphere exteriorly of. the casingi.

22; A fluid. transmission. comprising. aY casing havingrotatable primaryand secondary impeller members, rotatablef primary and' secondary turbine.,` members, and a normally stationa-ryfluid guide member therein.. all of. said. membersv cooperating'withi aworking fluidfor'setting upV a fluid`lvvork'ingcircuit. in a` closed. toroidal path` for the transmissionofitorque, .means vconnected with the guidemember.' andlforming: a' pair` of annular Ventilatingr chambers: respectively positioned on cppositesides. of one le'gof theuidworking cirlcuit; ant annular valvev movable. to' interrupt the luvvy of: Working? fluidin said circuit, .means includingf a: chamber. formed in said. guide. member im: mountingfsaidvalve; a Ventilating;` passage for said chamber; and means'to connect the-ventilating: chambers; and the Ventilating passage tothe atmosphere. exteriorly of the casing.

23'; A fluid" transmission: comprising av casing having rotatable4 primary andZ secondary impeller members, rotatable primary ands secondary turbine members, and a normally stationary fluid guide: memberV therein, all` of2 said members cooperating withY a Working iiuid' for setting'up a fiuidf Working' circuit in' a closed path forthe transmission of torque...V said secondary i-mpeller and turbinemembersbeing annular in formand beingY provided with annular Ventilating chambersdisposed withirrtheI casing, and means connecting said chambers tothe-atmosphere exteriorly of the'casing.

24; A" controlling mechanism for amotor vehicle of the typeA having a throttle controlled engine, ai driving shaft, a driven shaft, and a throttle; controlling element, ai hydraulic. power transmission. for transmitting' torqueY from the drivingto the. drivenshaft. said transmission including a. single casing; having rotatable impeller and; turbine membersi and a: normally stationary fluidiguiding `member: `therein allcooperative With af-workingffluid to'establishfa Working circuit havinga) closedl pathv Within thecasing-valve means carried by'l said: huid guiding; member: and movable in; the casing to variably restrict the flow of? fluidiy lin said. circuiti and thereby varyA the torque; transmis'sion;` and? means controlled. by movementof. saidthrottle controllingelement for movlng said valve? means.

25. A hydraulic variable speed power transmis- 'sioni comprising a casing; containing. a working fi'ui'd; a rctatablezbladedzprimary impeller for directing' said: fluid: radially." outwardly, a. radially extending bladed. primary turbine for receiving the radially directed. uid; a: blad'ed rotatable secondary impelle'r arranged' tot receivev the iiuid exhaustedI fromthe primary turbine; increase its velocity andl t'o exhaustsaid fluid in an axial direction, means connected. With the primary imp'eller forrotating' the: secondary impeller in a direction. opposite to* that-of. the primary impeller, a rotatabl'efblade'd'secondary turbine for receiving the fluid exhausted'. from theI secondary impeller, and for directing the fluid to how in a path havingthe same direction as-thedirection of`- rotation: of the' primary` impellen. and a. fluid guide. member for" receiving the fluid from the secondary turbine and-for returning said uid to thep'rimary impeller.

26.- Ahydraulicvariable speedfpower transmissioni comprising.: au casing containing` a Working huid; a rotatablebladed primary mpeller. for. di.-

frectin'gz said fluid; radially.l outwardlyg.. means.. for

rot-ating; the primary impeller in: one direction, a radially extending bladedprimaryiturbineifor receiving theradially directed .uid and rotatable inthe samefdirectionas the primary impeller; a bladed rotatable secondary impeller arrangedto receive the-fluid exhausted'fromthe. primary turbine and to exhaust. said uid in an axial. direction,. means. connected with. the primary'impeller for. rotating. the secondary impeller. in. a direction opposite to that' of theprimaryimpeller; a rotata-ble. bladed secondary turbine for receiving theiiuid-r exhausted'. from the secondary impeller, and for directing the fluid in apath having the same. direction as the: direction .of rotation. of: the primary. impeller, andaiiuid. guide? member for receiving the: fluid from: the?. `secondary.l turbine and' for returning said'. fluid to: the primary impeller.

27.v A hydraulic'variablespeed power transmission; comprisinga casing containing a. Working fluid; a rotatable bladed. primary impeller for directing said fluid.' radially outwardly, means for rotating thev primary' impeller in one direction, a radially extending bladed primary turbine for receiving the radially directed uid and rotatablel in the same direction as the primary impeller, al bladed rotatable secondary impeller arranged toreceive the fluid exhausted'from the primary turbine and to exhaust said iiuid in an axia-l direction, means connected with the primary impeller for rotating the secondary impeller in adirectioncppositeto that of the primary impeller, alr'otatablebladed secondary turbine for receiving the iiudf exhausted from the secondary impeller, a iiuidi guide member for receiving. the uid from the-secondary' turbine and for returning said fluid to the'primary impeller, and means operablev at will. tov restrict the circulation of iiuid while the impellers and turbines continue to'rotate.

28; A controlling mechanism for a motor` vehicle of thetype: havingv a throttle controlled engineg. a' driving shaft, a'v driven: shaft,. and. a throttle controlling element, ay hydraulic power transmission for transmitting torque from the driving tothe driven shaft,.said transmission including a single casing: having; rotatableA impeller and turbine members and a normally stationary iiuid guiding member'therein all Cooperative with a Working uiclV to establish a Working. circuit having a closed. path; Within the casing; valve means.` carried. by said: uid guiding; member and movable` in the casingr` to variablyl restrict the flow of. uid. in` saidV circuit. and. thereby vary the torque transmission, and means .controlled by movement of said throttle controlling element when movedin' a throttle closing direction to move said valve means to stop the. ow of fluidin said circuit; thereby stopping the transmission ofV torquev from the.` driving to the driven shaft and thus neutralizing the transmission.

29.` A controlling mechanism for. a motor vehicle of the type having a. throttle controlled engine, a driving shaft, a driven shaft, and a throttle controlling element, a hydraulic power transmission for transmitting torque from the driving. toY the.` driven shaft, said transmissionincluding asingle casi-ng having rotatable impeller and' turbine members and a normally stationary fluidguiding member therein all cooperative With a working uid to establish a working circuit-having a closedl path Within the casing, valve* means.` carried by said uid guiding member and movable: in. the.f casing t@ variably restrict. the

ilow of fluid in said circuit and thereby vary the torque transmission, and means controlled by` movementl of said throttle controlling element beyond the full open throttle position to move said valve means to partially restrict the flow of fluid in said working circuit.

30. A controlling mechanism for a motor Vehicle of the type` having a throttle controlled engine, a driving shaft, and a driven shaft av torque transmission, means controlled by move-r` ment of said throttle controlling element upon movement thereof in said controlling rangey for moving said valve means to restrict said iiow, and power means operable to move said valve means to open position upon movement ofv the throttle controlling element from said controlling range to said throttle operating range.

31. A controlling mechanism for a motor vehicle of the type having an engine, a drivingshaft, a driven shaft, and a brake mechanism, a hydraulic power transmission for transmitting torque from the driving to the driven shaft, said transmission including rotatable impeller and turbine members and a normally stationary fluidguiding member all cooperative with a working fluid to establish a working circuit having (av closed path, valve means carried by said fluid guiding member and movable to stop the iiow of fluid in said circuit and thereby arrest the torque transmission, a brake operating member, means for mounting said brake operating member for movement in a rst range and for movement in a second range, means controlled by movement of said brake operating member upon movement thereof in said first range to move said valve means to stop the ow of fluid in said circuit, and means controlled by movement of said brake operating member upon movement thereof vin said second range for applying said brake mechanism to stop the vehicle and arrest movement of said driven shaft.

32. A hydraulic variable speed power transmission comprising a casing containing a working fluid, a rotatable Vbladed primary impeller for directing said fluid radially outwardly, a radially .l

extending bladed primary turbine for receiving the radially directed fluid, a bladed rotatable secondary impeller.' arranged to receive the fluid exhausted from the primary turbine, increase its velocity and exhaust said fluid in an axial direction, means connected with the primary impeller for rotating the secondary impeller in a direction opposite to that of the primary impeller, a rotatable bladed secondary turbine for receiving the fluid exhausted from the secondary impeller, directing the fluid axially therethrough, and exhausting said fluid to flow in the same direction as the direction of rotation of the primary impeller, and a fluid guide member for receiving the fluid from the secondary turbine and for returning said fluld to the primary impeller.

33. A hydraulic variable speed power transmission comprising a casing containing a working fluid, a rotatable bladed primary impeller for directing said fluid radially outwardly, a radially extending bladed primary turbine for receiving the radially directed fluid, a bladed rotatable secondary impeller arranged to receive the fluid exhausted from the primary turbine, increase its velocity and exhaust said fluid in an axial direction, means connected with the primary impeller for rotating the secondary impeller in a direction opposite to that of the primary impeller, a rotatable bladed secondary turbine for receiving the fluid exhausted from the secondary impeller, said secondary impeller and said secondary turbine being positioned at a greater distance from the axis of rotation of all said impellers and turbines than the primary impeller and the primary turbine, and a fluid guide member for receiving the fluid from the secondary turbine and for returning said iiuid to the primary impeller to complete a fluid working circuit.

34. A power transmission mechanism as set forth in claim 33 which includes in addition, an output member, and means interconecting said turbine members to deliver the combined torques of said turbine members to said output member.

35. A power transmission mechanism as set forth in claim 33 which includes in addition, a driving shaft connected with the impellers, a driven shaft connected with the turbines and means operable at will for directly connecting the driving and driven shafts.

36. A power transmission mechanism as set forth in claim 33 which includes in addition, means operable at will to variably restrict the circulation of fluid in said working circuit while the impeller members are rotating.

37. A power transmission mechanism as set forth in claim 33 which includes in addition, means for cooling the fluid including a cooling chamber positioned interiorly of said working circuit.

EDWARD J. THURBER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,319,752 Brown Oct. 28, 1919 1,327,080 Brown Jan. 6, 1920 1,551,055 Rieseler Aug. 25, 1925 1,855,967 Jandasek Apr. 26, 1932 2,014,944 Martyrer Sept. 17, 1935 2,042,189 Robe May 26, 1936 2,067,793 Siebold Jan. 12, 1937 2,102,755 Sinclair Dec. 21, 1937 2,104,608 Cox Jan. 4, 1938 2,205,794 Jandasek June 25, 1940 2,235,672 Dodge Mar. 18, 1941 2,270,536 Lenning Jan. 20, 1942 2,280,015 Tipton Apr. 14, 1942 2,340,494 Smirl Feb. l, 1944 2,341,921 Jandasek Feb. 15, 1944 2,377,825 Teagno June 5, 1945 2,379,015 Lysholm June 26, 1945 2,388,329 Jandasek Nov. 6, 1945 2,457,692 La Brie Dec. 28, 1948 2,492,456 Becker Dec. 27. 1949 2,516,385 Hodge July 25, 1950 

